Red-eye, a condition caused by direct flash photography, results when light from a camera's flash reflects off the retina of a human eye. The light is reflected by red blood cells in the retina. The pupil of the eye appears bright red in a photograph.
Various techniques are available for correcting red-eye in digital images. Most techniques involve manually identifying the affected region of an eye, and desaturating the red pixels in the affected region.
Often, the red-eye correction is not visually pleasing. It would be desirable to correct red-eye in a manner that is visually pleasing.